Dr Sam Holford is one of around 3000 resident doctors who are striking against long working hours, unsafe working conditions and poor pay.
He's two years out of medical school and now works at North Shore Hospital.
In the two weeks leading up to the strike, Mr Holford worked 12 shifts in a row. Several of those were 15-hour days.
On the first Saturday, he was the only doctor in his ward. By the seventh day he was becoming fatigued and forgetful.
"I was reminded by two or three separate nurses about medications I'd forgotten to chart or changes on the plan that I hadn't actioned," Mr Holford told Story.
Mr Holford says the long stretches affect his attention span.
"When I am really tired... I can't listen to the patients properly. I find myself not daydreaming but just not listening, not hearing what they are saying."
He says when he's that tired, he wouldn't want himself to be his doctor.
"Even my colleagues, the most respected ones, when they're tired, they are awful. I wouldn't want them treating me or my family or anybody else."
The doctors are asking for the maximum number of days they work in a row to be cut from 12 to 10, and the number of night shifts in a row reduced from seven to four.
The District Health Boards say they are happy to cut down the long stretches junior doctors work, but want some flexibility in negotiations.
Mr Holford says people's lives are at risk when doctors cannot concentrate on the treatment of patients.
"You do a morning night round and you see what the night staff have done, they've chartered antihypertensives four times and made doses that are twice or 10 times as big as they should be.
"We have enough checks that most of those get stopped but we all know of these mistakes making it through."
A survey of resident doctors found 275 had fallen asleep at the wheel. Sam Holford is among them.
"I don't feel safe driving, I've had one episode when I certainly did fall asleep at the wheel and I was woken up when I hit the bumpy lane marking," he says.